1. Field of the Invention
The present invention relates to a semiconductor device in which mounted components mounted on a metal pattern on a substrate are encapsulated with an epoxy resin.
2. Background Art
A technique for improving the productivity and reliability of power semiconductor devices by encapsulation with an epoxy resin in which a filler is dispersed is coming into widespread use. However, the intimacy of contact of the epoxy resin with solder and the metal pattern is unsatisfactory and separation occurs starting from the interface therebetween. Therefore, stress due to expansion and shrinkage of the epoxy resin acts on wires, electronic mounted components and semiconductor chips when a heat history is applied, resulting in separation and changes in characteristics of the semiconductor chips.
Under such circumstances, a technique to prevent resin slippage around wires and semiconductor chips by providing slits in a metal pattern on a substrate such that an anchor effect is produced has been proposed (see, for example, Japanese Patent Laid-Open No. 2006-32617).